A heap dump analysis tells a suspect is org.apache.sling.models.impl.ModelAdapterFactory loaded by org.apache.felix.framework.BundleWiringImpl$BundleClassLoaderJava5 [2].

https://github.com/Adobe-Marketing-Cloud/asset-share-commons

One instance of "org.apache.sling.models.impl.ModelAdapterFactory" loaded by "org.apache.felix.framework.BundleWiringImpl$BundleClassLoaderJava5 @ 0x9749d5d0" occupies 1,528,764,960 (78.49%) bytes. The memory is accumulated in one instance of "org.apache.sling.models.impl.ModelAdapterFactory" loaded by "org.apache.felix.framework.BundleWiringImpl$BundleClassLoaderJava5 @ 0x9749d5d0".